PCA9555

The PCA9555 is an NXP 24-pin CMOS device that provides 16 bits of general-purpose parallel input and output expansion for the I2C bus and the SMBus, in a 24-pin package. It was developed to enhance the NXP family of I2C I/O expanders, and it gives a small host sixteen extra ports that it can read or drive over the two-wire bus, with an interrupt output that tells the host when an input changes so it does not have to poll. The device includes an internal power-on reset, a set of configuration registers that make each port an input or an output, and it provides a strong sink and source current that suits an LED or a small load. Three address pins allow up to eight expanders on one bus, so a designer can add I/O in blocks of sixteen without a larger host, and the ESD protection and the industrial temperature range suit a control and a consumer application. Typical applications include an industrial control board, a consumer and an appliance product, a server and a networking system that must add buttons, LEDs, relays or control lines. Every device BeiLuo ships is factory-traceable and includes an import declaration, a certificate of origin and a RoHS compliance file. Our FAE team helps you choose the ports and plan the addressing and the pull-ups.